Archive Issue

2014, Volume 24, Number 2

Brief Update: New Test Offerings in DNA-Based
Non-Invasive Prenatal Testing (NIPT)

William G. Finn, MD, Medical Director, Warde Medical Laboratory

In a previous Warde Report, we introduced the Panorama non-invasive prenatal screening test (NIPT) for as an option for our clients. [1]   In partnership with Panorama, we are now happy to offer additional options for NIPT. In addition to the existing screen for aneuploidy (trisomy 21, trisomy 18, trisomy 13, and monosomy X), Panorama now offers a screening panel for congenital syndromes related to specific chromosomal microdeletions, including DiGeorge syndrome (deletion 22q11.2), Angelman and Prader-Willi syndromes (deletion of portions of chromosome 15q), Cri-du-chat syndrome (deletion of a portion of chromosome 5p), and the 1p36 deletion syndrome. 

Unlike fetal aneuploidy, these microdeletion syndromes are not a function of maternal age and have a consistent populational frequency across maternal age groups. In aggregate, these syndromes have a combined incidence of approximately 1 in 1,000 live births. 

The most common of these syndromes (DiGeorge syndrome) affects approximately 1 in 2,000 live births, likely exceeding the incidence of cystic fibrosis. When filling out the required requisition / information sheet, practitioners will now have a choice as to whether to include microdeletion screening in addition to aneuploidy screening when ordering the Panorama NIPT (Warde test code: PANOR).  According to the manufacturer, microdeletion analysis through the Panorama assay offers detection rates of 93 to 99%, depending on the specific deletion. [2]

Microdeletion analysis will now be offered as a separate additional option, with a separate charge.  As a result, the base price of the Panorama NIPT screen for aneuploidy has been reduced.  For additional information, please contact Warde client services.

References

  1. Finn WG: DNA-based non-invasive prenatal testing (NIPT) for fetal aneuploidy.
    Warde Report 2013; 23(1):1-6.

  2. Hall MP: PanoramaTM non-invasive prenatal screening for microdeletion syndromes. http://www.panoramatest.com/en/system/files/Panorama%20Microdeletions%20White%20Paper.pdf